* {
	margin: 0px;
	padding: 0px;
	box-sizing: border-box;
	/* background-color: #f7f7f7; */
	background-color: #fff;
}


#layout {
	display: flex;
	flex-direction: column;

	width: 90%;
	margin: 0 auto;

}


/* border-radius */
#main .left-side,
#top,
#main .left-side li,
#main .main-content li {
	border-radius: 4px;
}

#top {
	/* height: 50px; */
	/* width: 100%; */
	
	/* 设置 交叉轴 高度 */
	flex: 0 0 50px;
	background-color: yellow;

}